KeepassXC-Browser is blocked by apparmor in Tor Browser.
This seems stupid especially since KeepassXC comes by default with Whonix.
I eventually got it working but it would be great if better minds than I could make it work without needing scary manual changes from the defaults.
I wrote about what I had to do to get it working at github Kicksecure apparmor-profile-torbrowser issues 14 (sorry not allowed to post URLs - guess I’m too new).
and it shouldnt work, integrating x add-on into TB will give changes that will effect the browser fingerprint thus it wont be support by default.
you can disable apparmor if that annoys, but there should be no upstream behavior change.
I just allowed the particular keepassxc-proxy executable to run in apparmor, so I didn’t disable apparmor completely.
This is documented.